1. Field of the Invention
This invention relates to a sheet-material feeding device used in an image forming apparatus, such as a copier, a laser-beam printer, a facsimile apparatus or the like.
2. Description of the Related Art
As shown in FIG. 11, in a conventional copier, serving as an image forming apparatus, a main body 500 of the copier is divided into a lower frame 500a and an upper frame 500b. The upper frame 500b is supported so as to be openable/closable relative to the lower frame 500a, so that the main body 500 of the copier can be widely opened for the ease of jam removing processing, maintenance and the like. An automatic original-feeding device 600 is openably/closably mounted above the main body 500 of the copier. The automatic original-feeding device 600 feeds an original S placed on platen glass 501, serving as an image reading unit, and discharges the original S after it has been read. In the automatic original-feeding device 600, when a bundle of originals S is inserted into a sheet-feeding port 601, and a copying button (not shown) on the main body 500 of the copier is depressed, a lifter 604 is raised by driving means (not shown), and the originals S are individually separated by a roller 605 and a pad 606 and are sequentially conveyed onto the platen glass 501.
In the above-described conventional apparatus, there is no holding means for immobilizing the bundle of originals S by pressing it when the bundle of originals S is inserted into the sheet-feeding port 601 of the automatic original-feeding device 600. Hence, when the main body 500 of the copier is widely opened in the above-described manner, the originals S may move in the direction of an arrow J, and in the worst case, may drop from a tray 602.
In order to prevent such phenomena, for example, a configuration in which the angle .alpha.10 made by the bundle of originals S set on the tray 602 and the horizontal line L is set to a large value, or a configuration in which a drop preventing wall 603 for regulating the rear end of the bundle of originals S can be considered. Such a configuration, however, results, for example, in an increase in the production cost.